A Simple Rule of Thumb for Diffusion on Transition-Metal Surfaces

Department of Chemical and Biological Engineering, University of Wisconsin–Madison, Madison, Wisconsin, United States
Angewandte Chemie International Edition (Impact Factor: 11.26). 10/2006; 45(42):7046-9. DOI: 10.1002/anie.200602223
Source: PubMed

ABSTRACT On the surface: Diffusion on transition-metal surfaces plays a key role in the transport of atomic and molecular species on catalytic surfaces. Density functional calculations show that there is a simple linear relation that allows the prediction of the diffusion barrier from the binding energy of the diffusing species on the respective metal surface. (Figure Presented).

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    • "Therefore, a relatively fast diffusion of atomic oxygen may also be expected at the pressures and temperatures of interest here. This suggestion is also supported by a rule of thumb for diffusion of small atoms and molecules (like H, N, O, CO, NO) on metal surfaces, which predicts that the diffusion barrier is only about 0.12 times the adsorbate binding energy [26] "
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